Numerical investigation of heat transfer enhancement and entropy generation of natural convection in a cavity containing nano liquid-metal fluid

摘要

Investigation of natural convection heat transfer enhancement and entropy generation of nano liquid-metal fluid in a differentially heated cavity is carried out for three types of nanofluids, copper-Ga (Cu-Ga), diamond-Ga (Diam-Ga) and carbon nanotubes-Ga (CNT-Ga), in which Grashof number varies from 10(4) to 10(6) and nano particles volume fraction from 0.01 to 0.15. The nanofluid flow is simulated by the two-phase mixture model. The studied results show that the convective intensity, heat transfer and local entropy generation increase with the increase of Grashof number. The average Nusselt number of nano liquid-metal fluid increases monotonically with increasing of Grashof number and nanoparticles volume fraction, and the total entropy generation also increases monotonically. The heat transfer performance of CNT-Ga is the highest, that of Diam-Ga is the second and the Cu-Ga is the lowest.